Thallium(III) bromide, also known as thallic bromide, is made of thallium in its +3 oxidation state and bromide ions. It disproportionates at a low temperature to thallium(I) bromide and bromine. It can be made by reacting thallium(I) bromide with bromine in water or an organic solution.

Thallium(I) triiodide, a black crystalline solid. It does not contain thallium(III), but has the same structure as CsI3 containing the linear I3- ion.